ATC500R "Build Thread"

[JasonB]

[JasonB]

Judging by the damage I need a new piston at the very least lol. There appears to be at least one cold seize on this set up

[volfan537240]

Who gobbed all that rtv under the base gasket?

[Louis Mielke]

No lube holes for the bridge, cast piston I guess?

[JasonB]

Cast indeed. She appears to be stock somewhat.

The rtv massacre came from the previous owner that Mr Clean bought the original CR5 from

[JasonB]

i dont think the pictures point out the damage to the piston very well; there are some pretty extensive gouges on the piston but the rings look ok so im not sure if there was a siezure at one point and they just stuck some new rings on the piston and kept running the motor. I can still see the cross hatch in the bore though and theres not any marring of the walls so they may have cleaned it up. The motor didnt feel like it ran as hard as I would hope a 500 should. I want to split the cases tonight and get into the transmission and see how badly grooved my clutch basket is. And according to info from the cr500 boards, my water pump seal failed and that is why it started leaking lol i had no idea where the coolant was coming from but apparently there is a weep hole under the water pump cover incase the seal fails so it doesnt destroy the bearing.

items on my shopping list as of right now:

Top end rebuild
replace whatever parts are bent/broken in the tranny that make shifting miserable
Rekluse Z Start Pro
2001 clutch cover/case to replace the magnesium stock 88 case
seal and bearing rebuild kit for the entire motor
consider having a CPI pipe built as the evil twin to Mr350x's

[Louis Mielke]

No, all CR500s are iron liner cylinders.

Judging by the marks on the cases I'm guessing something might have come loose in there once upon a time. That's a plated bore, right? If so you should be able to clean it up with some acid and a Scotchbrite pad, or sandpaper if there are no chips in it.

[Louis Mielke]

So whats the status on this Jason? I'm curious how bad it was smoked after you held it wide open for 10 minutes at the herk and jerk at trikefest. I swore that engine was complete toast after it stopped running.
Nearly brought a tear to my eye as I witnessed that happening.

[JasonB]

I put another 5 hours of ride time on it after TF this year at Badlands and at my buddies rock quarry. Last Sunday Eric split the cases. Sending the cases, cylinder, and head off to Adam Millar for a TWIRP port job and to have the head milled. I bought a Rekluse Z-Start Pro last friday, found a 'deal' on them. Motor is getting a good clean up, new bearings and seals, and anything else I can think of. My new Right Side crank case showed up last thursday as well. Still waiting on APT to get their act together and ship me the cast 38mm smartcarb i preordered almost 4 months ago. Hoping to have it back together mid December, just in time for cold weather lol. And I beat it at trikefest because I had plans to rebuild it, probably not the best way to go about it. thanks for askin!

[JasonB]

some random pics for you guys

the right side crank case clutch cover from the newer 90 and up models was required since the 1988 case half I had didnt allow for the larger updated clutch basket width. For the new Rekluse clutch I had to pick this part up, its shiny and honda fresh



measured out the bore on this cylinder and found it to be right at 89.1mm which is basically stock bore size. The other pic below shows us a pro-x piston though, so someone had it apart to throw a new piston in at some point.

[JasonB]

[JasonB]

All that having been said, if you don't chew Big Red than Meow.

[Dirtcrasher]

Don't trust that digital caliper, use your micrometer and an inside bore gauge.

And don't drop it and shatter the face None of my verniers have "0" at 12:00

[bkm]

Now go home and get your meow shine box.

[JasonB]

I actually ended up buying two rekluse z-start pro clutch kits, one is going to my engine builder as part of the payment for services lol. pretty crazy to look at two of these beautiful clutches, im stoked to get this thing back together and go ride with both the newly released smartcarb from APT and this clutch! and a fresh engine. Just need to get the frame powdercoated lol